This disclosure relates to an optical outer diameter measurement apparatus.
An optical outer diameter measurement apparatus is disclosed (refer to, for example, JP-U-62-174210 and JP-A-59-83007). This optical outer diameter measurement apparatus is designed such that a light beam reflected and converted into scanning light by a rotary mirror is collimated by a collimator lens, and an object to be measured is disposed between the collimator lens and a condenser lens, thus making it possible to measure the dimensions of the object to be measured.